OK. I think bullet protrussion into the case is a bigger factor an chamber length goes right along with how deep to seat the longer bullets. I'm not a wizzard with this stuff, but I can see your point.

My 260 design wouldn't change bullet protrusion but it would improve neck tension. It may even loose a small amount of velocity. The 6.5 Creedmoor has some bullet protrusion into) the powder
Depending on the leade and bullet weight. I don't know how much that really maters .. Consistant neck tension does help reduce standard deveation in velocity.

Neck tension is a huge factor wthen trying to reduce Standard Deviation, either resistant or smooth straight accross the load. Too much is an issue for pressure problems, but I think a person would stop and rethink the reloading procedures. My 300 win mag is tighter than my 308, but I'm sure it's becuase of the dies. I only full length resize every 4 loads. My Thompson 300 win mag is really fussy about that. If I don't FL resize by the 4 th reload. They will enter the chamber just fine, but need a ram rod to remove them. I always cut them back to length on every load and debur. Thompson Ventures have a tight chamber. They also varry greatly from gun to gun. Out of 3 Venture's, all 300 win mags in our family, my nephew and i can reload for each other, but my bother's Venture could not be reloaded for at all. A call to the factory accomplished nothing, so the gun went down the road, hopefully to a hunter who doesn't try to reload. Well, I'm getting closer to the sweet load for my FCP-K 308. 44.5 gr. of Varget, 155 Sierra Match produces nice groups @ 2792 in 25 degree weather. I may back it off a little to see if they tighten up. Only 100 rds through the tube at this point, following all the break-in rules. It's getting there. They cancelled our shoot for tomorrow because of the weather, "WET". My philosophy came out of the Army, "If it ain't raining, it ain't traing" . The heavy guns $ don't like it when it's wet CFT, get that CM shooting out to 500 yds and see what kind of groups you get.

I'm pretty poor on vision. Can't drive without corrective lenses. Not just legally. I'm over 50 . I also have spine damage that causes plenty of pain when in prone position. But, I still want to do it. I want to stay in the 500$ or less for the scope. Does a guy sling up tight for prone target shooting? ?. I'm thinking a heavy laminated stock would flex less. I don't know big the targets are and as it will be summer, mirage is a possible problem. .

I've been following this thread as I'm thinking about a new LR stick, and I wanted to comment about scope selection. I'm in my mid 50s and my eyesight is going, so I've been forced to move towards optical sights. I've gotten back into long range shooting and spent a long while sorting out my optical options. To make a long story short, I have been impressed with the Burris MTAC 3.5 x 10 x 42 scope.

I am a long time Leupold fan, and own a few Leupold scopes, but Leupold did not offer a scope that did what I wanted at any price, so I started looking around. With some trepidation, I settled on the Burris MTAC, which performs well at distances out to 1200 yards. I have one season of fairly extensive practice and use for unknown distance matches; the clicks and adjustments are repeatable, the image clarity is excellent and I really like the mildot reticle. I have mine mounted on a Warne 20 moa base, with 30 mm Burris rings lapped in, so I can use about 60 minutes of elevation out of the 80 the scope offers. I liked the scope enough that I decided to use one on my .50 BMG. So far it has held up well on that, too, but I haven't shot it enough to recommend it for that use.

If I were going to spend more and get more performance, I probably would jump to the Nightforce rather than play around with anything less. The Burris is as good as any of the lesser priced scopes that I have used, and I have tried a lot of different ones. (Leupold, Bushnell, Nikon, SWFA, among others) It was exactly what I wanted in a medium to long range tube. I'm going to put one on my Swede and on my other long range rifles. Some folks would have you think that more magnification is better, but the real thing is having everything in focus and having a really clear image. If you've got that, you're most of the way there. I've had no trouble picking up a 4" steel plate at 500+ yards with that scope, when guys with scopes costing 3x as much had trouble seeing the target. Plus, when targets AREN'T a thousand yards away, it's nice to have the option for less magnification.